🧹 [Code Health] Remove unused Dict import in census_extractor.py

[Data-Science-Link]

🎯 What: Removed unused Dict import from typing in data_engineering/data_sources/census_acs/census_extractor.py.
💡 Why: Dict was imported but not referenced anywhere in the file. Removing unused imports improves code readability and maintainability.
✅ Verification: Verified the code changes using grep and ran the script census_extractor.py and compiled the script. The code compiles properly without any syntax errors.
✨ Result: The code is cleaner, more readable and has better codebase health by getting rid of unused dead code.

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PR created automatically by Jules for task 11337318028040496762 started by @Data-Science-Link

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[github-actions]

🔒 Security Scan Complete

Code Security: ✅ Checked with Bandit
Dependencies: ✅ Checked with pip-audit

All security checks passed! See Actions logs for details.

[github-actions]

🔒 Security Scan Complete

Code Security: ✅ Checked with Bandit
Dependencies: ✅ Checked with pip-audit

All security checks passed! See Actions logs for details.